This invention relates generally to coin selecting and separating devices, and in particular to a selection device for detecting edge surface characteristics such as serrations.
In the known prior art, the separation of serrated and smooth-edged coins has been effectuated by modifying the well-known coin cradle as is disclosed for example in U.S. Pat. No. 3,120,300. Coin cradles, which are basic to coin selecting devices of the type under discussion, are useful for separating coins on a basis of size and weight. Selected coins are then directed into a predetermined path for further tests, such as the magnetic test for metal differentiation. Modification of the coin cradle so that it will perform the additional functions of accepting or rejecting coins on the basis of whether or not they have serrated edges obviously presents certain problems. Such a modified cradle, for example, is not easily susceptible to fine adjustment with regard to its new function of detecting coin serration, except at the risk of affecting the balance of the cradle. This balance, of course, is necessary if the cradle is to perform its original functions of size and weight separation adequately.
Serration detectors of this general type are disclosed in U.S. Pat. Nos. 3,592,307 and 3,598,217, owned by the same assignee. In these serration detectors, the feeler is comprised of a thin spring steel blade insert molded into a zinc base die cast or plastic body. This spring steel blade is then trimmed to length after molding. Because of variation in blade material and production trim equipment, the condition of the detector blade surface operating on the coin edge is of variable and inconsistent quality. This variable produces erratic and unpredictable operation of the serration detector in the final acceptor assembly, such that smooth edge slugs may be accepted as genuine coinage and/or genuine coinage may be rejected as slugs.